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Comment by dirktheman | Hacker News Reader

What's even more mindboggling is that, through combining multiple data streams, wireless transfer speeds of over 1 terabit/second seem to be possible. However, what really blew my mind is that their total budget is just 2 million euros. Pocket change compared to the n-th cat pic sharing app that just got funded.

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Depends on your bandwidth. For most real world applications, you're probably going to hit the Shannon limit at much lower data rates.

For example, with 1GHz of spectrum (a huge amount compared to WiFi (40MHz for 802.11n) or LTE (20MHz)), with an excellent 50dB signal to noise ratio, you can never move more than 16.61 gigabits per second.

True, but if I recall correctly spatial multiplexing can be used to increase channel capacity.

Using the same 50db SNR for WiFi at 40Mhz we get:

  ((40000000)*(log(1+100000)/log(2)))
  ans =  6.6439e+08

or 664Mbit/s, however, 802.11ac can achieve higher than that by using MIMO. I unfortunately don't know the formula for max channel capacity for multiple streams.

It doesn't seem like they are using this though in their experiment.

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